E X T O X N E T
Extension Toxicology Network
A Pesticide Information Project of Cooperative Extension Offices of
Cornell University, Michigan State University, Oregon State University, and
University of California at Davis. Major support and funding was provided
by the USDA/Extension Service/National Agricultural Pesticide Impact
Publication Date: 10/97
TRADE OR OTHER NAMES
The active ingredient propamocarb hydrochloride is considered a carbamate
fungicide, however, it is not a methyl carbamate anddoes not inhibit cholinesterase.
Some trade names for products containing propamocarb include Banol, Prevex,
Previcur, Tattoo C, Tattoo M, Dynone, Filex, and Proplant. Formulations come as an
aqueous concentrate (1, 2, 3, 6).
Propamocarb is a registered active ingredient with the U.S. Environmental
Protection Agency (EPA), which has been undergoing reregistration. Propamocarb is
currently registered by EPA for non-food uses on turf and ornamentals as Banol (2).
Outside the U.S., the active ingredient is used on tobacco, vegetables,
strawberries, potatoes and other crops. Propamocarb is considered a general use
pesticide with a toxicity classification of IV (relatively non-toxic). Check with
specific state regulations for local restrictions which may apply. Products
containing propamocarb must bear the signal word "Caution" on their label (3).
Propamocarb is a specific fungicide with specific activity against several
Oomycete species which cause seed, seedling, root and stem rots and foliar diseases
in many edible crops and ornamental plants. The mode of of action is different
compared to other Oomycete fungicides, which provides for efficacy against strains
that have developed resistance to other fungicides. Crops include potatoes, turf,
and ornamentals (1, 2).
There are no acute toxicity concerns with propamocarb. The acute rat oral LD50
was 2,900 mg/kg in males and 2,000 mg/kg in females. The acute rat dermal LD50 was
less than or equal to 3,000 mg/kg. The acute (4-hour) inhalation LC50 in rats was
>7.9 mg/l. Propamocarb was not a skin sensitizer in guinea pigs. Based on these
results, propamocarb hydrochloride was classified as Toxicity Category III for acute
oral and dermal toxicity, and eye irritation, and Category IV for acute inhalation
toxicity and skin irritation (4).
In a 90-day feeding study, propamocarb was administered to albino rats at
concentrations of 0, 20, 50, 100, and 500/1,000 ppm in the diet. The only effects
noted were slightly reduced food efficiency and body weight gains at 1,000 ppm (4).
In a 90-day feeding study in beagle dogs, propamocarb was administered in the
diet at concentrations of 0, 50, 100, 500, and 1,000/2,000 ppm. No treatment-related
findings were observed (4).
A 21-day dermal toxicity study was performed with propamocarb in Sprague-
Dawley rats at dose levels of 0, 100, 500 and 1,000 mg/kg/day, 6 hours per day, 5
days per week over a 21-day period. No treatment related effects were observed (4).
A 21-day dermal toxicity study was performed with propamocarb in rabbits at
dose levels of 0, 150, 525 and 1,500 mg/kg/day, 6 hours per day, 5 days per week,
over a 21-day period. The No-Observed-Effects-Level (NOEL) for this study was
considered by the Agency to be 150 mg/kg/day based on dose-related skin irritation
in mid- and high-dose animals and a decrease in weight gain in mid-dose females (4).
A 2-year feeding chronic toxicity/carcinogenicity study was performed in
Sprague-Dawley rats with propamocarb at dietary concentrations of 0, 40, 200 or
1,000 ppm. There was no evidence of carcinogenicity or other treatment-related
effect except for a possible reduction in food intake in female rats at the highest
level tested. Thus, 1,000 ppm (41 mg/kg/day) was considered to be the NOEL (4).
A 2-year feeding chronic toxicity/carcinogenicity study was performed in CD-1
mice with propamocarb at dietary concentrations of 0, 20, 100 and 500 ppm. No
evidence of carcinogenicity or toxicity was noted at any dose level. Thus, 500 ppm
(53 mg/kg/day for males and females, respectively) was considered to be the NOEL (4, 6).
A 2-year feeding study was performed in beagle dogs with propamocarb at
dietary concentrations of 0, 1,000, 3,000, 10,000 ppm. Decreased weight gain,
decreased food efficiency and an increased incidence of acute gastric mucosal
erosions and/or chronic erosive gastritis were noted in all treated groups. Thus, a
NOEL for this study was not determined but was considered to be slightly lower than
the lowest dose level tested (33.3 mg/kg/day) (4).
In an investigation on rats over three generations, propamocarb hydrochloride
caused no effects at concentrations up to 1000 ppm (1).
In a developmental toxicity study, rats were administered propamocarb by
gavage at dose levels of 0, 74, 221, 740, or 2,210 mg/kg/day on gestation days 6-19.
The NOEL for maternal toxicity was 740 mg/kg/day based on mortality, clinical
observations and decreased body weight gain at 2,210 mg/kg/ day. The NOEL for
developmental toxicity was 221 mg/kg/day based on increased post-implantation loss,
decreased fetal weights and increased incidence of minor skeletal anomalies
(retarded ossification) at 740 and/or 2,210 mg/kg/day (4).
In another developmental toxicity study, rabbits were administered propamocarb
by gavage at dose levels of 0, 15, 45, 150, 300, or 600 mg/kg/day on gestation days
6-18. The NOEL for both maternal toxicity and developmental toxicity was 150
mg/kg/day, based on decreased maternal body weight gain and increased post-
implantation loss at 300 mg/kg/day (4).
A three-generation reproduction study was conducted using rats fed a diet
containing propamocarb at dietary concentrations of 0, 40, 200, and 1,000 ppm for
100 days and then continuously through 3 successive generations. No treatment-
related effects were noted on either the parents or offspring (4).
Oral dosing of pregnant rats with 680 and 2040 mg/kg body weight of
propamocarb hydrochloride was toxic to the dams and the conceptus. The NOEL was 204
mg propamocarb hydrochloride/kg body weight.
Oral dosing of pregnant rabbits with 280 mg/kg body weight of propamocarb
hydrochloride was also toxic to the dams and the conceptus. The NOEL was 164 mg
propamocarb hydrochloride/kg body weight (1).
No evidence of genotoxicity was observed in a battery of studies including
Salmonella and E. coli gene mutation assays, 2 mouse micronucleus assays, an in
vitro mammalian cytogenetic assay using cultured human lymphocytes, a yeast mitotic
gene conversion assay and a yeast mitotic recombination assay (1, 4).
In dietary rodent studies, propamocarb hydrochloride showed no evidence of
No special studies have been conducted to investigate the potential of
propamocarb to induce estrogenic or other endocrine effects. However, the standard
battery of required toxicity studies has been completed. These studies include an
evaluation of the potential effects on reproduction and development, and an
evaluation of the pathology of the endocrine organs following repeated or long-term
exposure. These studies are generally considered to be sufficient to detect any
endocrine effects yet no such effects were detected. Thus, the potential for
propamocarb to produce any significant endocrine effects is considered to be minimal
Fate in Animals and Humans
Labelled material was administered orally to rats. Propamocarb hydrochloride
is rapidly absorbed and almost totally excreted, predominately via the urine (>90%
within 24 hours). Mineralization takes place via oxidation and hydrolytical
Effects on Birds
The investigations on the acute and subacute toxicity of propamocarb
hydrochloride gave the following values:
Acute toxicity (LD50 in mg/kg body weight): mallard duck >6289 mg/kg, pheasant
Subacute toxicity (5 day LC50 in mg/kg food): mallard duck 12,915 mg/kg,
pheasant >25,000 mg/kg, Japanese quail >25,000 mg/kg.
Propamocarb hydrochloride can be classified as non-toxic to birds (1).
Effects on Aquatic Organisms
Fish. Acute toxicity studies fo the acive ingredient in various fish species
gave the following LC50 values after 96 hours: mirror carp 235 mg/l, rainbow trout
410-616 mg/l, bluegill sunfish 415 mg/l.
Daphnia. Toxicological investigations of propamocarb on the water flea gave
the following values: 48 hour EC50 of 295 mg/l, 48 hour No Observable Effect
Concentration (NOEC) of 126 mg/l.
Algae. A laboratory investigation of the effects of propamocarb on green
algae at 20C resulted in the following values: 96 hour EC50 of 350 mg/l, 96 hour
NOEC of 22 mg/l.
It is concluded that propamocarb hydrochloride is of very low toxicity to
aquatic organisms (1).
Effects on Other Animals (Nontarget Species)
Earthworms: The effects of propamocarb on earthworms were investigated using
artificial substrate and the compost worm. The 14-day LC50 was >1000 mg/kg soil.
Propamocarb can be classified as non-toxic to earthworms.
Bacteria: In a cell multiplication-inhibition test conducted on Pseudomonas
putida, propamocarb only reduced cell multiplication at concentrations higher than
145 mg/l water. Consequently, propamocarb is only of very low toxicity to bacteria.
Soil micro-organisms: Investigations were conducted with propamocarb as 722
g/l aqueous solution at a concentration 10 times the commercially recommended dose
rate. There were no adverse effects on dehydrogenase activity or nitrification (1).
Breakdown of Chemical in Soil and Groundwater
Propamocarb hydrochloride does not persist in the soil. Following an adaption
phase, it is rapidly decomposed by micro-organisms. The average half-life is less
than 30 days; 90% of the original material is decomposed within less than 70 days.
The material does not leach and with the mineralization being so rapid, the
compound does not contaminate the groundwater, even under favorable conditions (1).
Breakdown of Chemical in Surface Water
Propamocarb hydrochloride is very stable to hydrolysis and photolysis in
sterile aqueous media. However, aquatic micro-organisms rapidly decompose
propamocarb hydrochloride (up to 97% within 35 days). The material is also bound to
the sediment, desorption is relatively weak (1).
Breakdown of Chemical in Vegetation
The metabolism of propamocarb hydrochloride was investigated using labelled
material in tobacco, lettuce, cucumbers, potatoes, and ginger. The greatest part of
the detected material was unchanged parent compound, with the other detected
radioactivity coming from compounds produced by the plant by incorporation of
labelled CO2 derived from soil-decomposed propamocarb hydrochloride (1).
Metabolism studies in potatoes, cucumbers and spinach demonstrated that
propamocarb is degraded into carbon dioxide which is reincorporated into natural
plant constituents. The primary residue found in all crops is the parent compound
propamocarb hydrochloride (4).
Residue trials on potatoes indicated that residues of propamocarb in potatoes
from foliar applications were below the Limit of Quatification (LOQ), at 2.5 times
the maximum proposed label rate. No measurable residues of propamocarb were detected
in any of of the processed commodities following treatment at 2.5 times the maximum
proposed label rate and a shorter than proposed pre-harvest interval (4).
PHYSICAL PROPERTIES AND GUIDELINES
Technical propamocarb hydrochloride is crystalline and colorless. It is
considered slightly corrosive to metals. It has a weak aromatic odor. The active
substance is highly hygroscopic and therefore very difficult to handle (1, 3).
|LEL: ||1000 ppm (33.3 mg/kg/day) Dog (4)
|RfD: ||0.11 mg/kg/day (4)
|CAS #: ||25606-41-1
|Chemical name: ||Propyl [3-(dimethylamino)-propyl]carbamate-hydrochloride (1, 3)
|Chemical Class/Use: ||carbamate compound used as a systemic soil and foliar fungicide for control of Oomycete diseases (5)
|Solubility in water: ||1005 g/L at pH 7 (3)
|Solubility in other solvents: ||Soluble at 20[ring] C in acetone 560 g/L, methanol >500 g/L, isopropanol >300 g/L, ethyl acetate 23 g/L, hexane <0.1 g/L, and toluene <0.1 g/L (2)
|Melting point: ||45-55[ring] C
|Vapor pressure: ||8 x 10-4 Pa at 25[ring] C
|Partition Coefficient (Kow): ||0.84
AgrEvo USA Co.
Little Falls Centre One
2711 Centerville Rd.
Wilmington, DE 19808
Review by Basic Manufacturer:
Comments solicited: June, 1997
Comments received: July, 1997
Technical Information Bulletin for Propamocarb Hydrochloride. Fourth
edition. 1995. Hoechst Schering AgrEvo GmbH. Berlin, Germany. 15 pp.
New York State Section 18 Emergency Exemption for Propamocarb on Potatoes.
1996. Cornell University. Ithaca, NY 14853-0901.
Farm Chemicals Handbook. 1997. Meister Publishing Co. Willoughby, OH
U.S. Environmental Protection Agency. Pesticide Tolerance Petition for
Propamocarb. Federal Register Document 97-5681. Tuesday, March 11, 1997.
W.T. Thomson. 1997. Agricultural Chemicals. Book IV: Fungicides. 12th
edition. Thomson Publications, Fresno, CA 93791.
Review by Agrevo USA Company. July 21, 1997.